The present invention relates to a sheet post treatment apparatus applied to a stapler sorter attached to the sheet discharge part of an office machinery, like a copying machine or a facsimile, and comprising multiple bin trays which, through ascending or descending operations at regular intervals, successively separate and carry sheets discharged from said sheet discharge part by or in the order of pages and stapling sheets received in said bin tray and, in particular, relates to an sheet host treatment apparatus aligning sheet received in said bin tray for stapling within certain limits.
A traditional sheet post treatment apparatus, like the one proposed in the U.S. Pat. No. 5,090,673, is briefly explained in the following, using FIGS. 1 and 2.
FIG. 1 is a perspective view which roughly shows one embodiment of a traditional sheet post treatment apparatus and FIG. 2 is a top plan view which shows the operation of the traditional sheet post treatment apparatus.
In FIGS. 1 and 2, the numbered parts are the following: 101 bin unit housing, 101A vertical frame, 101B lower frame, 102 bin cover, 103 bin slot, 104 bin roller, 105 bin tray, 106 slot, 107 upper arm, 108 lower arm, 109 rotation center shaft, 110 sector gear, 111 aligning rod, 112 aligning rod driving motor, 113 output gear, 114 alignment reference plate, 115 stapler.
As shown in FIGS. 1 and 2, when the sheet discharge part discharges sheets, the sheet post treatment apparatus applied to a stapler sorter moves and aligns the sheets to a site available for stapling. To said sheet discharge part are attached the bin unit housing 101 consisting of a vertical frame 101A and a lower frame and the designated bin cover 102 whose two side ends are supported by vertical frames 101A. The bin tray 105 is equipped with two bin rollers 104 which move up and down along bin slots 103 formed in rear vertical frames 101A' of said bin unit housing 101 and the fan-shaped slot 106 of designated size is formed in a designated site of said bin tray 105. To one side of the bin cover 102 and the lower frame 101B are attached two ends of the rotation center shaft 109 which forms one unit with the upper arm 107 and the lower arm 108, and the circular arc-shaped sector gear 110 is equipped in the lower end of the lower arm 108 of said movement center shaft 109. The aligning rod 111 is connected to the upper arm 107 and the lower arm 108 of said rotation center shaft 109 and equipped to be inserted in the slot 106 of said bin tray 105. The aligning rod 111 is rotated to move and align sheets discharged from the sheet discharge part to one side of the bin tray 105 for stapling by the stapler 115.
The aligning driving motor 112 is equipped in a designated lower end part of said bin unit housing 101 and is impressed and driven by an external power supply. The output gear 113 equipped in the shaft of the aligning rod driving motor 112 transmits driving power engaged with the sector gear 110.
The alignment reference plate 114 in FIG. 2 is equipped at one side of the bin tray 105 and helps the alignment of one side of the sheets moved to the stapling site of said stapler 115.
The aforementioned traditional sheet post treatment apparatus moves and staples sheets discharged from the sheet discharge part and received in the bin tray at the stapling site of the stapler by an aligning rod rotated by the driving power of the aligning rod driving motor.
The aforementioned traditional sheet post treatment apparatus executes sheet alignment by being equipped with a separate driving power source for the sheet stapling but said separate driving power source and additional driving power source control devices enhance manufacturing costs and require additional space for attachment, thus results in the problem of having a big machinery size. In particular, small size machinery having sheet sizes of two varieties or less have less efficiency regarding increased costs and additional space and a problem in that it is impossible to align sheets having sizes beyond the coverage of rotation capacity of the aligning rod.
Another type sheet post treatment apparatus was suggested to implement sheet stapling in a small size machinery having sheet sizes of two varieties or less.
FIG. 3 is a block diagram of the essential parts showing one embodiment of this type sheet post treatment apparatus and FIG. 4 is a cross-sectional view from side `A`.
In FIGS. 3 and 4, the numbered parts are the following: 131 bin tray, 132 tab, 133 bin tray pin, 134 aligning rod, 135 slot, 136 copying sheet, 137 sheet discharge site.
As shown in FIGS. 3 and 4, multiple bin tray 131 carry sheets 136 discharged from the sheet discharge part through ascending or descending operations at regular intervals. The bin tray 131 has a rectangle-shaped slot 135 formed on the top side of the bin tray and is equipped with an aligning rod 134 having a predetermined position and being inserted into said slot 135. The aligning rod 134 has parts of designated length forming an inclined side to one side at a predetermined angle to help the alignment of the copying sheets 136 discharged when the bin tray 131 moves up and down to receive sheets.
Examining the operation of the sheet post treatment apparatus according to said structure, copying sheets 136 discharged from the sheet discharge part of office machinery like a copying machine are carried in the bin tray 131 by its own weight thereof and then the bin tray 131 carried with copying sheets 136 moves up and down and, during said processes, one side of copying sheets 136 carried in the bin tray 131 is moved to a stapling site (not shown in FIGS. 3 and 4) by the inclined side of the aligning rod 134 and stapled.
A traditional sheet post treatment apparatus structured and operated through aforementioned processes enables a saving of installation spaces and a cut in manufacturing costs by simply transforming the shape of the aligning rod inserted in the slot of the bin tray, thus allowing the alignment of the copying sheets without a driving power source but it has two main problems: first, the sheet alignment by the inclined side is not effectively executed due to factors like a bending of copying sheets carried in the bin tray during the alignment process and second, the sheet alignment implementation by the structural formation of the inclined sides of the aligning rod is not flexibly adapted to various sheet sizes.